Artificial foot



April 1955 F. w. DALTON 2,705,807

ARTIFICIAL FOOT Filed March 29, 1954 a F radar/ck W Dalton //8 V INVENTOFP. flwmfi'm v y fiMl- United States Patent ARTIFICIAL FOOT Frederick W. Dalton, Boise, Idaho Application March 29, 1954, Serial No. 419,419

6 Claims. (Cl. 331) This invention relates to an artificial foot, and more specifically provides an improved structure wherein the artificial foot has a more natural movement thereby forming a more comfortable and easily used foot.

An object of this invention is to provide an artificial foot which is simple in construction, comfortable in use, universally movable within limits, well adapted for its purposes and relatively inexpensive to manufacture.

Another object of this invention is to provide an artificial foot having substantially a natural movement wherein there is no strains placed on the leg stump or the wearers groin due to walking on uneven surfaces.

A still further object of this invention is to provide an artificial foot having a minimum of parts and requiring no bolts or fastening members to assemble and which is constructed of inexpensive materials.

These, together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure l is a perspective view showing the artificial foot of the present invention positioned in a shoe with portions of the shoe being broken away showing the details of construction of the artificial foot;

Figure 2 is a partial section taken substantially along the longitudinal center line of the artificial foot of the present invention showing the details of construction of the ankle member with the projection thereon and the recessed foot member; and

Figure 3 is a detailed transverse section taken substantially along section line 3-3 of Figure 2 showing the details of construction of the longitudinal pin and its association with the longitudinally curved groove.

Referring now specifically to the drawings, it will be seen that the numeral generally designates the artificial foot of the present invention for positioning in a shoe 12 and secured to members of an artificial leg or to members for securing the artificial foot 10 to a leg stum T111286 members are generally indicated by the numeral 14 in Figure l of the drawings and are secured to an ankle member 16 which is pivotally attached to a foot member 18. The foot member 18 is generally in the shape of the main portion of a persons foot and includes a substantially cylindrical recess 20 on its upper surface that extends transversely of the foot 18 and is tapered from one end to the other. The ankle member 16 includes 2. depending projection 22 which is substantially cylindrical in cross section and tapered from one end to the other for transverse sliding engagement with the tapered recess 20. It will be seen that the recess 20 extends about the major portion of a circle that is more than a semicircle and engages the periphery of the projection 22 about the major portion thereof wherein the projection 22 cannot be pulled directly out of the recess 20 but may be only disengaged therefrom by lateral movement therefrom. The outer end or lower end of the projection 20 is provided with a groove 24 which extends longitudinally of the projection 22 and curves longitudinally as indicated by the numeral 26 and the arcuate groove 24 is also transversely curved in substantially a semicircular condition for receiving a longitudinal pin 28 positioned in a longitudinal bore 30 in the ice foot member 18. The connecting members 14 are secured to each side of the ankle member 16 by suitable fastening members 32 positioned in suitable bores 34. The side members of the connecting members 14 extend beyond the juncture between the projection 22 and the recess 20 for engaging the sides of the foot 18 for resiliently restricting the transverse pivotal movement of the foot 18 in relation to the ankle member 16. A separate toe element 36 is provided for positioning in the shoe 12 and the bottom edges of the toe 36 and the foot members 18 are normally in contacting relation as indicated by the numeral 38. The adjacent end walls 40 of the toe 36 and the foot member 18 diverge when the foot is in its normal position and when a step is taken the toe pivots about an axis formed by the juncture 38 until the adjacent ends 40 engage thereby giving a natural movement to the toe member 36. Further, it will be seen that the foot member 18 may pivot in relation to the ankle member 16 about a transverse axis substantially passing through the center of the projection 22. In addition to this, the foot member 18 may pivot about a longitudinal axis due to the particular fit of the projection 22 within the recess 20 wherein the peripheral walls thereof are in spaced relation thereby permitting limited rocking movement about a longitudinal axis. Further, it will be seen that abutment members 42 are provided for limiting the pivotal movement about a transverse axis wherein a natural walking step may be taken with the artificial foot 10 of the present invention. It will be understood that the artificial foot 10 may be constructed of suitable strong light-weight wood, metal, or plastic, as desired. It will be seen that the natural movement of the artificial foot of the present invention removes the excessive strain on the leg stump and also removed the strain on the groin muscles of the wearer thereby providing an easily used and more comfortable artificial foot.

From the foregoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claims.

What is claimed as new is as follows:

1. An artificial foot comprising a foot member having a recess in the upper surface, an ankle member having a projection on the lower end thereof for pivotal reception in said recess, a separate toe member positioned forwardly of the foot member, said recess and projection being generally circular with the recess engaging a major portion of the periphery of the projection, a groove in the outer end of the projection, a bore extending longitudinally of the foot member in alignment with said groove, and a pin positioned in said bore and groove for retaining the projection in the recess.

2. The structure as defined in claim 1 wherein said groove is longitudinally curved to permit pivotal movement of the projection and ankle member about a transverse axis. 7

3. The structure as defined in claim 1 wherein said groove is transversely curved to permit pivotal movement between the foot and ankle members about a longitudinal axis.

4. The structure as defined in claim 1 wherein abutment means is provided for limiting relative pivotal movement between the foot member and ankle member.

5. The structure as defined in claim 1 wherein said recess and projection are tapered for transverse sliding engagement and provided with spaced peripheral walls to permit limited universal movement between the ankle member and foot member.

6. The structure as defined in claim 1 wherein said toe and foot member are provided with adjacent end walls that normally contact each other at the bottom edge and diverge upwardly for contact when the toe member is pivoted upwardly.

No references cited. 

